In Journal 2 of the Earth Cycle project, we insisted on the fact that Paris Region produces around 30 million tons of DCW (Demolition and Construction Waste) per year, including 25 million tons of inert waste, including around 18 million tons of excavated earth per year. The creation of the infrastructures of the Grand Paris Express (GPE) and the town planning operations linked to it will generate even greater production in the coming years: it is expected that 60 million tons will be generated by the Société du Grand Paris (SGP) by 2030. These volumes demonstrate the need for the development of research and innovation actions on a regional scale but also implementation strategies on large scales have to be discussed and elaborated.
This important volume of earth (i.e. four Pyramids of Khufu), must be extracted, transported and valued in a smart and sustainable way. This topic seems to have been completely neglected in urban planning and urban development for the past 30 years, with some exceptions, while it used to be a part of the spontaneous regeneration of urban spaces in the previous periods, as mentioned before. Earth Cycle is an active contributor in an attempt to implement circular economy logic in urban planning. The actors mobilized around this action offer this possibility.
The objective of this journal is to discuss Earth cycle duplication and scaling up strategies in an attempt to address the problems regarding excavated earth management in the Paris Region. Developing an approach to use these soils as a construction material is a large contribution in the development of circular economy in the Parisian region. The duplication of the pilot proposed and implemented by the Urban Innovation Action’s project in Sevran is a major issue for the coming period. Scaling up a pilot is an important element of the success of the UIA project.
The choice to deal with this theme was naturally necessary because the UIA Earth Cycle ends on 10/30/2021 and one of the perspectives to be implemented would be the duplication of the pilot in other territories. This journal analyzes this perspective and the strategy proposed through actions of promotion, communication, dissemination of knowledge but above all the development of the factory and the cooperative society.
Earth Cycle proposes to reuse and to valorize the excavated earth to produce building materials with low environmental impact. A raw earth materials factory located in Sevran was designed and built. This factory will produce from autumn 2021 blocks of compressed earth, mortars and coating.
During the UIA project, many initiatives to organize the earth construction sector have been revealed necessary in parallel with the construction of the factory, so that the pilot finds its place in a local ecosystem first then towards a regional scale. These actions relate to three major categories:
- Technical Certification of materials’ performance.
- Calculation of their ecological footprint for integration in a Life Cycle Assessment. Three documents of an Environmental and Health Declarations for masonry walls and coating were elaborated.
- The training of architectural professionals and the building sector to the use of materials.
The creation of the Sevran pilot factory is only a first step. The purpose of the UIA project is to test an innovative solution, by creating a knowledge base and skills, in order to then be able to generalize it. The figure 1 proposed by the Earth Cycle team, demonstrates the need of 30 production sites on the scale of the Parisian region. This estimation is based on two criteria; the potential estimated by local authorities and urban developers from one side the availability of construction materials. In this journal, we discuss these models and options.
The figure shows the map of the Parisian region and an estimation of the market potential for earth construction.